LUKE ENTO 201

How many main tagmata does the insect body have and what are they called?

3 - head, thorax, abdomen

How many fused segments make up an insect's head?

6

What can be found on the head on an insect?

compound eyes, ocelli (light receptive organ), antennae, mouthparts

What is the head used for?

Sight, eating, tasting, brain, feeling/touching (antennae, tiny hairs)

How do insects smell?

On the antennae, there are lots of tiny little hairs that have gaps in the cuticle. The water insoluble odorant binds with the water soluble odorant binding protein and enters through those tiny gaps to reach the receptors inside the hair and make its way to the olfactory nerve which then sends a signal to the brain.

How are insect mouthparts modified?

according to diet

What kind of mouthpart is this?

chewing

What kind of mouthpart is this?

sponging

What kind of mouthpart is this?

sucking

What kind of mouthpart is this?

piercing-sucking

How many segments make up the insect thorax?

3

How many pairs of leg are found on each segment of the thorax?

1 pair per segment

Where can an insect's wings be found?

On the posterior (back) two segments of the thorax

Do all insects have the same kind of legs?

no, they can be greatly modified

What kind of legs can be found on this insect?

fossorial front legs on a mole cricket (Orthoptera)

What kind of legs can be found on this insect?

saltatorial hind legs on grasshoppers (Orthoptera)

What kind of legs can be found on this insect?

raptorial front legs on mantids (Mantodea)

How many segments can be found on an insect abdomen?

usually 11

What does the abdomen contain?

digestive & reproductive organs, and it carries internal & external genitalia

Which tagmata does not have chemoreceptors?

thorax

What are the internal systems of insects?

peripheral nervous system, circulatory system, digestive system, respiratory system, & reproductive system

What is the peripheral nervous system?

sensory nerves moving information from receptors to the central nervous system; motor nerves that control muscles; and has stomatogastric nervous system that innervates the gut. (provides nerves to the digestive system inside the gut)

What are ommatidia and how many are there?

they are individual eyes inside a compound eye and can have up to 10,000 per eye.

What are tympanal organs used for?

hearing

Where can tympanal organs be found?

legs, wings, abdomen, and antennae

true or false: there are chemoreceptors found on the mouthparts

true

true or false: there are olfactory receptors on the antennae

true

What portion of the dorsal vessel is shown?

aorta

What portion of the dorsal vessel is shown?

heart

What are the internal organs of an insect bathed in?

haemolymph

How is haemolymph moved around the body?

by a dorsal combined heart and aorta

Which sections of the digestive system is lined with cuticle?

stomodeum (foregut) & proctodeum (hindgut)

What is the foregut called?

stomodeum

What is the midgut called?

mesenteron

What is the hindgut called?

proctodeum

Which section of the digestive system is unlined and is home to enzyme production & nutrient absorption?

mesenteron (midgut)

What is produced in the midgut?

peritrophic envelope to help protect the midgut since it is so thin

How does gaseous exchange occur?

Through a system of internal tubes called the tracheal system

Does blood play a role in the transport of oxygen?

no, oxygen is carried directly to its sites of utilization

How does oxygen enter the body?

through the spiracles

How many spiracles do insects have?

10 or fewer per insect

true or false: spiracles can be closed to prevent water loss

true

What are air sacs?

swollen trachae that can be pumped by body movement

How long do tracheae branch?

tracheae branch until they become intracellular tracheoles and are the site of gas diffusion

Is this the male or female reproductive system?

female

Is this the male or female reproductive system?

male

What is taxonomy?

the science of classification according to a pre-determined system, with the resulting catalog used to provide a conceptual framework for discussion, analysis, or information retrieval.

What does the Greek word "taxis" mean?

arrangement or division

What does the Greek word "nomos" mean?

law

What does a good taxonomy take into account when being developed?

the importance of separating elements if a group (taxon) into subgroups (taxa) that are mutually exclusive, unambiguous, and taken together, include all possibilities.

What does the pre-determined system use to classify insects into monophyletic groups?

homologies

What do all eukaryotes share in common?

cells have a nucleus

true or false: insects are ecdysozoans which are a type of protostomes

true

true or false: insects are most closely related to crustaceans

true

What clade are insects in?

Pancrustacea

What are the common ancestors of arthropods (including crustaceans & insects)?

trilobites (now extinct)

true or false: insects and crustaceans share the same body plan

true

What is Hexapoda classified as?

subphylum

How many orders of insects are there?

27

What does apterygota mean?

wingless insects

What does pterygota mean?

winged insects

How much of the total insect biodiversity does the apterygota (primitively wingless) make up?

less than 1%

What is the difference between the Dicondylia & Archaeognatha subclasses?

divergence in jaw structure. Archaeognatha has one point of attachment in the jaw and is monocondylic while the Dicondylia has two points of attachment in the jaw and is dicondylic

What does hemipterans (once considered 2 suborders) mean?

true bugs with sucking mouthparts

What is the standard tool for separating taxa?

dichotomous key

Hexapoda

six legs

Insecta

three-part body plan

Dicondylia

jaw attached at two points

Pterygota

with wings

Neoptera

wings can fold

Endopterygota

holometabolous development (AKA holometabola)

Orthopteroid orders

an older classification - grasshoppers, katydids, stick insects, praying mantids, cockroaches, mantophasmatodea

Hemipteroid orders

true bugs

Neuropteroid orders

Megaloptera & Neuroptera

What does "archaeos" mean?

ancient

What does "gnatha" mean?

jaw

What are the defining characteristics of Archaeognatha?

thorax humped, pair of cerci, and longer, central filament

What are the defining characteristics of Zygentoma?

abdomen with three roughly equal filaments

What does the Greek word "thusanos" mean?

tail

What does "ephemeros" mean?

short-lived

Ephemeroptera meaning

short-lived winged insect

Archaeognathta

bristletails

Zygentoma

silverfish

Ephemeroptera

mayflies

What are the defining characteristics of Ephemeroptera?

two pairs of wings, long cerci, and central filament. They also have aquatic nymphs.

Odonata

damselflies & dragonflies

What does "odont" mean?

tooth

What are the defining characteristics of Odonata?

short antennae, two pairs of richly veined wings, and aquatic nymphs

What does "pleiken" mean?

braided

Plecoptera meaning

braided wing

Plecoptera

stoneflies

Blattodea/blatta

cockroach

What does "iso" mean?

similar

Isoptera meaning

similar wing

Blattodea

cockroaches & termites

True or false: termites are just fancy cockroaches and have been reclassified scientifically but will keep their common name of termites

true

What does "grylli" mean?

cricket

What does "blatta" mean?

cockroach

Grylloblattodea

rock crawlers or ice crawlers

What does "mantis" mean?

prophet